Apparatus for boiling cellulose



Dec. 4, 1928.

. 1,693,983 (2. HANGLEIITER ET AL APPARATUS FOR BOILING CELLULOSE FiledAug. 10, 1925 Fig.1.

/n ven tor-s- Patented Dec. 4, 1928.

UNITED STATES PATENT, OFFICE.

- CARL HANGLEITER, OF' MANNHEIM-WALDHOF, AND .AJJOLF SCHNEIDER, OF KEL-HEIM-ON-THE-DANUBE, GERMANY, ASSIGNORS TO THE FIRM: ZELLSTOFFFABRIKWALDHOF, OF MAN NHEIM-WALDHOF, GERMANY, A CORPORATION OF GERMANY.

APPARATUS FOR BOILING GELLULOSE.

Application filed August 10, 1925, Serial No. 49,488, and in GermanyAugust 26, 1924.

Our invention relates to improvements in apparatus for boilingcellulose, and more particularly in apparatus of the type shown anddescribed in our copending application, Se-

, rial Number 549,112, filed April 3, 1922' As has been described in thesaid application cellulose boilers are provided with means forregenerating gases or vapors, such as sulfurous acid, and waste heat,such means consisting of a pluralityof pipes adapted to be connectedwith the top parts of the boilers and having a suitable liquid such asfresh liquor circulating therethrough, the said liquor taking up thegases and vapors escaping from the boilers and transmitting the same toa suitable storage receptacle. lVe have found that when connecting thesaid pipes with the boilers the operation of the system is frequentlyinterfered with by liquid blows caused at the part where the said pipesare connected with the conduits for transmitting the gas or vaporthereto. Further, the pressure of the said storage receptacle reacts onthe liquid circulated through the said pipes so as to interfere with theproper movement of the liquid. In some cases the fresh liquor is liableto flow into the boiler when the pressure within the said boiler hasbeen reduced to a certain extent. Finally the said pressure within thestorage receptacle, which is gradually increased in the course of theoperation by the increasing temperature of the fresh liquor, reacts onthe liquor and gas flowing through the said pipes and on the gasconfined within the boilers. The object of the improvements is toprovide a system in which the said objections are obviated, and withthis object in View we construct the said pipes for removing the gas orvapor from the boilers in the form of an injector or a plurality ofinjectors causing a vacuum within a vacuum chamber or chambers, andconnecting the boilers with the said'vacuum chamber or chambers, thesaid pipe or pipes including a pump for supplying the liquor to theinjector under pressure.

For the purpose of explaining the invention an example embodying thesame has been shown in the accompanying drawing, in which the samereference characters have been used in all the views to indicatecorresponding parts. 7 In said drawing,

Fig. 1, is a diagrammatical elevation showing our improved system, and

Fig. 2, is a detail sectional View showing the injectors, boilers, astorage receptacle and other parts of the system.

I In the example shown in the drawingfour improved system comprises aseries of cellulose boilers A, B, Z, a storage receptacle 1 4 for freshsulfit liquor, a pipe 12 connected with the bottom part of the saidreceptacle and having two branches 4 a=nd5 connected with suitablemixing members f and f disposed within the storage receptacle 14. Thepipe 12 includes a pump '11 and a regulating valve 16, and the pipes 4and 5 include pumps d and (Z and regulating valves 17 and 18. By meansof the said pumps and -regulating valves'the desired pressure differenceisproduced within the different parts of the pipes 12 and 4, 5. Betweenthe pumps d and d and the mixing members f and f1? check valves 6 and e?are provided, which prevent any reaction of the pressure within thereceptacle 14 on the liquor flowing through the pipes 4 and 5. Each ofthe boilers is connected with the pipes 4 and 5 through conduits a a 6 band 2 2 the said conduits including valves a, a 7), -6 and z, 2

As appears more particularly from Fig. 2 the pipes 4 and 5 includeinjectors c and 0 respectively, and in the example shown in the saidfigure. the suction chamber of each inj ector communicates with one ofthe conduits a a 6 b and 2 2 But we wish it to be understood that'ourinvention is not limited to a construction in which each of the saidconduits is connected to a suction chamber of its own.

In the operation of the system the waste gas or vapor and heat from theboilers A, B,.

Z are regenerated by opening the valves a, I

a, b", b and a, 2 and starting the operation of the pumps 11 and d", dThereby the fresh sulfit liquor from the storage receptacle 14 is madetoflow in the direction of the arrow ac first through the pipe 12 andthereafter through the branch pipes 4, 5. lVhen flowing through theinjectors 0*, 0

.the pressure of the liquor is transformed into Velocity, thus creatinga vacuum within the vacuum chambers of the injectors. Thereby the vaporand gas are drawn from the boilers and transmitted into the storagereceptacle 14, where they are mixed to the water by means of the members7, F, the said members being for example in the form of forami natedpipes, or in the form of pipes having nozzles at their delivery ends. Itwill be understood that after flowing through the first injector thevelocity of the liquor is again transformed into pressure, and it istransformed into velocity again when flowing through the next injector.

It .appears therefore that the waste gases and the heat from the boilersare stored Within the storage receptacle 14. 'Insome cases we providemeans in connection with the storage receptacle for rapidly removing alarge volume of steam by reducing the pres- In the operation of thesystem the pumps d? and (Z have thefunction to return the liquor intothe receptacle 14 and thus to assisttake the fresh liquor from the placewhere it is manufactured and pass the same into a receptacle such as 14without taking the same from the said receptacle and again circulatingthe same through the pipes. Also in such cases there is no reaction ofthe pressure within the storage receptacle on the liquor and gas withinthe pipes 4 and 5 and on the gas within the boilers A, B, Z.

While in describing the invention reference has been made to aparticular example embodying the same we wish it to be understood thatour invention is not limited to the construction shown in the drawing,and that various changes may be made in the general arrangement oftheapp'aratus and the construction of its parts Without departing fromthe invention. We claim:

1'. In a system for completely and rapidly relieving the pressure incellulose boilers and regenerating the waste heat and vapors, a boiler,an immediate connection between the waste gas-pipes and the liquor-pipessuch that an injector is formed by which the hot waste gases are drawnout of the boiler without cooling them, a pump for passing the, freshliquor under pressure through the said in jector, a closedstorage-receptacle from which the liquor is taken by the pump and intowhich it is fed back after having passed the injector, and a check-valvebetween said injector and storage-receptacle.

2. In a system for completely and rapidly relieving the pressure incellulose boilers and regenerating the waste heat and Vapors, a

boiler, an immediate connection between the waste gas-pipes and theliquor'pipes such that an injector is formed by which the hot wastegases are drawn out of the boiler without cooling them directly into aclosed liquor storage-receptacle, a pump between the storage-receptacleand injector for passing liquor under pressure through the saidinjector, and

a second pump between the injector and the storage-receptacle forfeeding back the liquor into the said receptacle.

In testimony whereof we hereunto aflix o'ur signatures.

CARL HANGLEITER. ADOLF SCHNEIDER.

